An apparatus of the above type is disclosed in DE Patent publication No. 1 752 749 corresponding to U.S. Pat. Nos. 3,592,038 and 3,714,808. In that disclosure, the stand of the apparatus is supported by means of support legs which lean against a pipe and are arranged to be displaced relative to said stand by means of a feed screw for producing a vertical movement mechanically during the collaring operation. Such an arrangement is practical for manually operated equipment but it is not the best possible solution for large equipment with fixed stands and intended for mass production. The vertical movements of working heads, i.e., both downward displacement of means for making a hole and upward displacement of shaping means for making a collar, require different optimum speeds.
Thus, the object of the present invention is to provide a structurally simple apparatus, wherein said vertical movements can be controlled and programmed to be optimum in various steps of operation.